I was wondering about is the seal holding the kyuubi. When Naruto tries to remove it Minato suddenly appears and stops him. What might be a possibility is that when Minato sealed the kyuubi in Naruto he added a part of a jutsu formula.
This jutsu formula was something that could allow Minato to teleport when the seal sensed distress. What I'm thinking is what if Minato added part of the Flying Thunder God jutsu formula into the seal that way when 8 tails were reached he would appear in Naruto's conciousness. Don't ask me how he can teleport into Naruto even though he is dead I guess he's just crazy strong and brilliant
Yes I did post this in the predictions but I got no feed back